1. Field of the Invention
This invention relates generally to medical devices and particularly to prosthetic devices which may be surgically implanted in a sterile condition. More specifically, the present invention relates to methods and apparatus for packaging such devices.
2. Brief Description of Background Art
Currently a wide variety of prosthetic devices are available for surgical implantation. The technology is advancing so rapidly that it is now possible to almost equal or perhaps even improve upon the operation of various organs through the implantation of artificial, prosthetic devices. These prosthetic devices are often made of materials which are compatible with human tissue so that the prosthetic device does not cause rejection from its host. As a result, a number of implants have silicone outer layers because of silicone's ready tolerance by the body.
There are presently a number of commercially available penile prostheses. These devices are inserted in the corpus cavernosa of the penis to produce an erection in men who would otherwise be impotent. The so-called rigid rod penile prostheses continuously assume a rigid state. In addition, other devices have been developed which enable the simulation of an erection and thereafter selectively assume a relaxed, non-erect state. Such devices include malleable penile prostheses, which may include a bendable wire or the like and inflatable penile prostheses. The inflatable penile prostheses generally include at least two fluid reservoirs, one of which stores a fluid prior to an erection and the other of which stores fluid during erection. The configuration of the reservoirs is such that the device is flaccid in one condition and erect in another condition. The fluid may be drained back to the original reservoir so that the penis may assume a flaccid state after erection.
The inflatable penile prostheses therefore generally include at least one bladder or reservoir which is filled with a liquid or a gas. Conventionally, the bladder is filled with a physiological solution compatible with the body. In the past, inflatable penile prostheses have been shipped to the surgeon for implantation in a dry state. When the surgion received the penile implant and was ready to begin the surgical procedure, it was first necessary to fill the prosthesis with sterile physiological solution. This often meant that the surgeon must measure the required quantity of fluid and then pour or otherwise load the fluid into the relatively small and sometimes difficult to handle prosthesis. A considerable waste of valuable surgeon's time results. Moreover, the possiblility of an inadvertent error in the loading procedure was always present. The manufacturer was therefore at a loss to insure reliable operation in the face of the surgeon's intervention.
It was believed to be necessary to ship the prostheses in a dry state because of the permeability of silicone. Silicone and other permeable materials enable fluids to interchange between the interior of the device and the surrounding environment, as when the contained fluid migrates outwardly or air migrates inwardly through a wall. Migration through the wall could upset the fluid volume required to precisely simulate an erection in operation. For example, if the fluid migrated outwardly of the device by osmosis, the required fluid volume might not be available so that the device would not work adequately. Similarly, if air was allowed to migrate inwardly, air bubbles could be created which might also adversely affect the operation of the device.
Thus, the inventor of the present invention appreciated that it would be highly desirable to provide a method and apparatus which permits the transportation of a prosthetic device in a fluid filled state so that the necessity for loading the fluid into the prosthesis, for example in the operating room, is avoided.